Question

我正在制作一个用户输入决策树，我想强制将输入进行比较的字典改为小写。我把.lower（）放在不同的地方并且不断出错。

not_found = True
while True:
    if OPTIONS == "1" or 'a':
        ARTIST_PICK = str(raw_input(
            "Please pick an artist\n"
            "Or Q to quit: ")).lower
        print ARTIST_PICK

        **entries = allData(filename).data_to_dict()
        for d in entries:
            arts = d['artist']**

        if ARTIST_PICK in arts:
            print "found it"

        elif ARTIST_PICK == 'q':
            break

        else:
            print "Sorry, that artist could not be found. Choose again."
            not_found = False

这是我试图降低“条目”的示例，并将用户输入与以下内容进行比较：

[{'album': 'Nikki Nack', 'song': 'Find a New Way', 'datetime': '2014-12-03 09:08:00', 'artist': 'tUnE-yArDs'},]

Answer 1

如果您的问题只是比较艺术家的名字，那么您可以使用列表理解来使所有内容都小写。

entries = allData(filename).data_to_dict()

if ARTIST_PICK in [ d['artist'].lower() for d in entries ]:
    print("found it")
elif ARTIST_PICK == "q":
    break
else
    print("Sorry, that artist could not be found. Choose again.")

或者，如果您更倾向于使用for循环（为了便于阅读而重新安排一点）：

if(ARTIST_PICK != 'q'):
    entries = allData(filename).data_to_dict()

    found = False

    for d in entries:
        if ARTIST_PICK == d['artist'].lower():
            found = True
            break
        elif ARTIST_PICK == "q":
            break

    if(found):
        print("found it")
    else:
        print("Sorry, that artist could not be found. Choose again.")
else:
    # handle the case where the input is 'q' here if you want

顺便说一下，作为一个原则问题，您应该将布尔变量命名为就像在句子中使用它们一样。如果找不到变量，请将变量not_found设置为False，而不是将名为found的变量设置为False或将not_found设置为{ {1}}。从长远来看，事情会变得更容易。

Answer 2

ARTIST_PICK = str（raw_input（ “请选择一位艺术家\ n” “或者Q要退出：”））。lower（）

在字典上强制用例来比较Python中的用户输入

2 个答案: